Engine cover screw won't budge

[NuttyJosh]

Hi guys any help would be really appreciated. So I have a screw that won't come out as I think the screw head is worn away on one side how do I go about getting it out. Thanks. Josh

 

[DomP182]

Is it one of the front easily accessed ones, as in can you cut a slot in it? They aren't or shouldn't be that tight